船舶二维测距定位中的GDOP分析

摘要

为了明确测距定位系统中锚点位置分布对未知点定位精度的影响情况,通过理论分析和模拟试验的方法对二维测距定位系统的几何精度因子(geometric dilution of precision,GDOP)进行分析,给出GDOP的计算方法和与GDOP值相关联的直观物理意义.分析认为,在二维测距定位系统中,当锚点的数量N一定时,GDOP仅与从未知点到锚点的单位向量有关,且GDOP值的平方与未知点到锚点的单位向量所构成的所有三角形面积的平方和成反比.在设计定位系统时,GDOP的值越小,系统的定位精度越高.%In order to clarify the influence of anchor nodes' location upon the location accuracy of blind nodes, by means of theoretical analysis and simulation tests the geometric dilution of precision ( GDOP) in two dimensional location system based on range was analyzed.A new method for GDOP put forward and the physical meaning of GDOP value was represented.It is shown that the GDOP is just related to the directions from the blind node to anchor nodes, the square of GDOP made an inverse ratio to the quadratic sum of triangle area constructed by any two unit vectors which are from blind node to anchor nodes.Analyzing GDOP is in favor of optimizing the configuration of anchor nodes, and improving the accuracy of location system.